Axially expansible rotary cutter



June 21, 1949. Djs. HORR 2,473,952

AXIALLY EXPANSIBLE ROTARY GUTTER Filed May l2, 1947 {w llllllll!INVENTOR Ell-Edf @HN/a L'. Ham' Patented June 21, 1949 UNITED STATESETNT OFFICE AXIALLY EXPANSIBLE RUTARY .CUTTER Daniel G. Horr, Spokane,Wash.

Application May 12, 1947, Serial No. 747,445

1 Claim.

My present invention relates to an improved axially expansible rotarycutter or dado head used in conjunction with a powered rotary arbor, andconsisting of two separating cutting elements formed with coacting meansthere-between so that the width of the groove to be cut may be varied byrotating the elements relative to each other.

In the accompanying drawings I have illustrated one complete example ofthe physical embodiment of my invention according to the best mode Ihave thus fai' devised, but it will be understood that various changesand alterations may be made in the exemplified structure within thescope of the appended claim.

In the drawings:

Fig. 1 is a side elevational View of the assembled cutter secured on arotary shaft mounted under a work table.

Figs. 2 and 3 are plan views of the cutter elements.

Figs. 4 and 5 are sectional views through the elements at the indicated.lines of Figs. 2 and 3.

Referring now to the drawings, I have illustrated the cutter C of myinvention secured on the shaft 2 by nut 4, and the housing 6 for theshaft is attached by anges 8 to the table I0. Pulley II provides for thetransmission of power to the shaft.

The cutter C comprises the opposed eccentric knives I2 extending fromthe center portion I4 which are bored at I6 to receive the shaft. Eachknife has a nose extension I8 formed with a flanged or transverse bit 20and these bits are arranged so that they face the same direction whenthe knives are assembled.

The center portions I4 of these elements are provided with coactingmeans including cam recesses 22 and cam ribs 24 concentric with thecenter bore and aligned to co-act with each other. The cam rib fits intothe cam recess and obviously as the elements are rotated relative toeach other through 180 the elements will be more or less spacedaccording to the position selected.

With the transverse flange bits extending beyond the thickness of theknives they will overlap considerably with the cutter elements in closerelation, while the overlap will be small when the cutters are spaced.Thus the width of the groove to be cut may be adjusted by a simplerotation of one or both cutter elements.

The collars or washers 26 and 28 will press the elements together whenthe nut is tightened and the cutter will be secured in adjustedposition.

While I have shown the cam elements as integral with the cutters it willbe obvious that separate cam disks or plates may be interposed betweenilat knives.

Having thus fully described my invention what I claim as new and desireto secure by Letters Patent is:

In a cutter head, the combination with a pair of rotary knives havingtransverse flange bits and circular center portions bored for mountingupon a shaft, of means on the adjoining faces of said center portionsincluding concentric, connected cam ribs on one knife and the otherknife having concentric, connected cam grooves to receive the ribs,whereby the distance between the knives may be varied from zero tomaximum by rotation of one knife relative to the other the ribs andgrooves providing an annular continuous contact between said knives.

DANIEL G. HORR.

REFERENCES CITED The following refcrenlces are of record in the nie ofthis patent:

